The present disclosure relates to a communication system and an operating method thereof, and particularly, to a communication system capable of controlling a remote terminal unit (RTU) of a supervisory control and data acquisition (SCADA) system and an operating method thereof.
A supervisory control and data acquisition (SCADA) system is defined as a communication system for collecting, receiving, recording, displaying, at a remote control center (RCC), state signal data (or points) of a plurality of RTUs using an analog or digital signal on a communication path and allowing the RCC to supervise and control each of the RTUs.
The SCADA system is typically a system for supervising and controlling, in a centralized manner, many kinds of remote facilities such as power generation, transmission, and distribution facilities, a petrochemical plant, an iron and steel making facility, and a factory automation facility, etc.
The SCADA system performs functions of a supervising system for performing a pre-determined operation according to a state of an RTU, for example, an alarm function, a supervising and controlling function for selectively operating the RTU manually or automatically, and an instructing function or displaying function of the supervising system for receiving, displaying, or recording a state signal of the RTU.
The RCC of the SCADA system periodically obtains a state signal (or state value) at determined times, generates system analysis information (or unique algorithm) used for controlling the plurality of RTUs on the basis of the obtained state signals, and controls each of the RTUs on the basis of the generated system analysis information.
Furthermore, the RCC may receive the state signal (or value) (“open” or “close”) from a cutout (a specific RTU) and at the same time, receive signal quality information (“good” or “suspect”) that is information including whether each state signal is normal or erroneous, generate analysis information on each RTU in correspondence to the received signal quality information, and may collect the analysis information on the plurality of RTUs to perform state estimation on lines provided with the plurality of RTUs.
The state estimation may be defined as specific information for controlling the lines provided with the plurality of RTUs.
However, in related art, there is a limit in matching the state estimation, since weights are given to each facility group. In detail, as illustrated in FIG. 1, the RCC converts each RTU data output from each of the plurality of RTUs (e.g. a transformer, generator, and load) included in each line into each RTU group data, corrects the each converted RTU group data by adding a weight for each RTU data, integrates the corrected RTU group data into line data, and performs state estimation on each of the lines on the basis of the integrated line data.
In this case, there is no choice to perform state estimation on the basis of each RTU group data, and since it is difficult to reflect each state data of each RTU included in each RTU group, there is a limitation of degradation in matching of the state estimation.
Moreover, the RCC may receive the state signal (or value) (e.g. “open” or “close”) from each RTU and at the same time, receive signal quality information (e.g. “good” or “suspect”) including whether each state signal is normal or erroneous, generate analysis information on each RTU in correspondence to the received signal quality information, and may collect the analysis information on each RTU to generate system analysis information that is analysis information on the plurality of RTUs.
In particular, while a data signal having quality of “GOOD” is output from a specific RTU, once a data signal having quality of “SUSPECT” is output, the data signal having quality of “SUSPECT” becomes used and matching of the state estimation becomes further lowered.